The discovery of a collection of ancient manuscripts in a cave near the Dead Sea grabs the attention of an eccentric millionaire by the name of Cail Lograft, provoking a chase for the truth that will rock the very foundations of the Catholic church. Soon, the intrepid archaeologist discovers that he is not alone. As the mystery unfolds, even the Vatican is drawn into a dramatic, unpredictable pursuit that takes Lograft all the way round the globe with the Egyptian mafia on his tail.

El Mentiroso (The Liar) is a blockbuster of a book, weighing in at almost 600 pages. At its presentation, the author described it as a thriller with a touch of Dan Brown about it. The following year, he unveiled his second novel: El Camino al más allá (The Road to Beyond). Now, the author's bio needs updating. Pepe Mel, it will say, was born in Madrid, Spain, in 1963, and he is the manager of West Bromwich Albion Football Club.

Mel certainly has a way with words. When his former club Real Betis lingered near the foot of the table last season, he publicly claimed that he would rather his teenage daughter announced she was pregnant than see his team relegated. Betis recovered brilliantly, while the remark said something about Mel's ability to communicate with the fans, creating a communion between stands and pitch. It also showed how much he cared.

Betis, after all, were his club. In fact, for much of the past three years, Mel was Betis. He had played for them, was top scorer in their 1989-90 promotion season, and when he finally departed for the second time in early December 2013, this time as a manager, he had been there for three and a half years – making him the longest-serving manager in Spain's first division. They had come a long way together: he had led them up from the Segunda División and into Europe, but by the time he was sacked Betis were bottom.

Two games before, they had been hammered 4-0 in the city derby against Sevilla. A clause in his contract, renewed in the summer, meant he could be released without compensation if the team went five consecutive weeks in the relegation zone. Now, it was applied. Yet no one celebrated his departure. On the day the sacking was made official, he was close to tears. Outside, fans threw rocks at the building in protest, while spray-painted messages blamed the board. No one blamed Mel.

When Mel took over at Betis they were, in the words of one player, "dead". The club was in administration, there was a legal battle over shares and ownership soon changed hands. There was a power vacuum and players wanted out. Mel had been chosen in part because, at less than €200,000 a year, he was cheap. He oversaw the restructuring of the club: older members of the squad were moved on, younger ones moved up. One player describes him as "brave – not afraid to ditch veterans or take on the dressing room heavyweights".

Álvaro Vadillo was 16 when he was given his debut. Beñat Etxebarria was not even getting in the B team at Betis; he is now at Athletic Bilbao, and a Spain international. No one wanted Adrián San Miguel, including Betis, but Mel kept him, gave him an opportunity through injury and stuck with him when he played well; now he is at West Ham. Swansea's Alejandro Pozuelo and José Cañas were among the 16 youth players who got first-team debuts under Mel. Don't rule out Mel returning to Betis for some Premier League debutants of his own.

At Betis at the time was Ryan Harper, the Spain-raised Scottish striker now playing at Algeciras. "What I most remember was the intensity of the sessions: if you dipped for a moment, he was on to you and he had no problem calling you out in front of the group," Harper says. "He wanted younger players who could run all day and he never wanted the ball lumped up the pitch; it was pass, pass, pass, all the time."

Possession and attack were the key. Betis were promoted as champions and top scorers. They also faced Barcelona in the Copa Del Rey. They were brave. At first it appeared that they had been perhaps a little too brave: they were praised for their performance at the Camp Nou but lost 5-0. In the return leg, they were 2-0 up when Jorge Molina missed a penalty, eventually winning 3-1. Pep Guardiola admitted he had been genuinely worried. "Without doubt they're one of the best teams we've faced," the then Barcelona manager said. "They've got good footballing taste."

Back in La Liga, Betis were among the most attractive sides to watch, usually employing a 4-3-3 formation and finishing a comfortable 13th. The 2012-13 season started with a 5-3 win at Athletic Bilbao and, although there were nervous moments and a painful hammering by Sevilla, they finished seventh, returning to Europe.

Mel's contract was extended but he no longer controlled signings, that responsibility now firmly in the hands of the sporting director, Vlada Stosic. Money remained tight; 14 players left and 12 came in this summer for a total outlay of only €3.5m. The top scorer, Rubén Castro, has been injured, the entire midfield had gone and half the squad was new, but there was little time for assimilation and there was European competition to play, too. Even luck appeared to have deserted them.

The relationship with the board had also become strained and when poor results followed, the ending, unlike that of The Liar, was all too predictable.